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Acids and Bases

Basic Techniques in Cell Biology and Biochemistry

The only problems that need to be done are numbers (3) and (4) on the second scanned document and the question below . Numbers (1), (2), (5) are finished problems that do not need to be done so problems (3) and (4) should be done using the same format (do Calculations and preparation)as those. Also please answer this ques

pH of a mixture of .001M sodium bicarbonate dissolved in water

How do you go about calculating the pH of .001M sodium bicarbonate (NaCO3) dissolved in water.....I some how derived the right answer which is pH = 8.3 but really have no idea how /i actually got the answer. How would I go about deriving the amount of [H+] so that I could use the equation [H+] = -log(???) = pH = 8.3

pH and Molarity

Please help with the following problems. a.) Giving the reason for your answer, which would you expect to have the higher value of pH, a 1.0M solution of the strong acid, HCl or a 1.0M solution of the weak acid, acetic acid, CH3COOH? b.) Why is it that we can say that ozone in the stratosphere is beneficial to

Particulates, Concentration and Combining Substances

a) A water sample contains 0.0700 grams of arsenic in 10.0L of water. What is the concentration of the arsenic in parts per million (ppm)? b) If a person breathes in 22m3 of air per day and the air contains 0.205 milligrams of particulates per m3 how many grams of particulates does the person breathe in per day? c) Expl

Stoichiometry Problems, Limiting Reagent, Acid/Base, Balancing Chemical Equations

1. A solution is prepared by dissolving 10.8g ammonium sulfate in enough water to make 100.0mL of stock solution. A 10.00mL sample of this stock solution is added to 50.00mL of water. Calculate the concentration of ammonium ions and sulfate ions in the final solution. 2. One of the most commonly used white pigments in paint

Quantative Analysis of Acid in Vinegar

Acid content of vinegar Flask 1 Flask 2 Inital volume of NaOH in burette 0 17.5 Final volume of NaOH in burette 17.5 35.3 Volume of NaOH used for titration

Acid Base Reaction and Oxidation Numbers

1) Pennies made after 1982 contain 97% zinc by mass. A student wants to prove this by filing the copper outside the penny until he sees zinc and then putting the penny in a 1.00 M HCl solution. The zinc will be oxidized and the H+ (from the HCl) will be reduced: Zn + 2H+ ----- Zn2+ + H2 If the entire pen

Molecular, Complete Ionic, and Net Ionic Equations

Write the molecular, complete ionic, and net ionic equations for the reactions that occur, if any, when solutions of the following substances are mixed: a.) nitric acid and barium carbonate b.) zinc chloride and lead nitrate c.) acetic acid and sodium hydroxide d.) calcium nitrate and sodium carbonate e.) ammonium chlorid

What is the limiting reagent? Questions about chemical reactions

Please show how to solve the following questions: 2Al (s) + 2KOH (aq) + 4 H2SO4 (aq) + 22 H2O (l) --> 2KAl (SO4)2*12H2O (s) + 3H2 (g) 12.0 g of Al, 420 mL 2.0M KOH, 216 mL H2SO4 placed in 300 mL ice bath (water in excess) 1) What is the limiting reagent? 2) How much aluminum is necessary to produce 18g of alum? 3)

Reaction between aluminum hydroxide and sulfuric acid

Solid aluminum hydroxide Al(OH)3 (s) reacts with aqueous sulfuric acid H2SO4 (aq) to produce aluminum sulfate Al2(SO4)3 (aq) and water. We combine 30.0g of Al(OH)3 (s) and 75.0 ml of 2.00 M H2SO4 (aq), and the reaction goes to completion. Subsequent analysis reveals that 12.3 g of Al2(SO4)3 was formed. What is the percent yield

Citric Acid and Fertilizer

Problem 1: Citric acid is concentrated in citrus fruits and plays a central metabolic role in nearly every animal and plant cell. How many moles of citric acid are in 1.90 qts of lemon juice *d=1.09 g/ml* that is 6.62% citric acid by mass? Problem 2: Nitrogen *N*, phosphorus *P*and potassium *K* are the main nutrients

Gas Laws and Stochiometry

1. How many significant figures does the sum of the following contain? 8.520 + 2.7? 2. How many moles of oxygen atoms are there in 10 moles of KCIO3? 3. The oxidation number of N in NaNo3 is? 4. What element is oxidized in the following chemical reaction? 3Cu + 8HNO3 ----> Cu(NO3) + 2NO + 4H2O 5. At what temp. will

Volume of Sulfuric Acid

What volume of 16 M sulfuric acid must be used to prepare 1.5 L of a 0.1 M sulfuric acid? a. 9.4 mL solution b. 9.4 L solution c. 16 mL solution d. 16 L solution

Benzoic acid with hydroxide ion - extraction with sodium hydroxide

Show an equation for the reaction of benzoic acid with hydroxide ion? If you were performing an experiment with a Grignard reagent phenylmagnesium bromide with dry ice (carbon dioxide) in ether to create benzoic acid, why would it be necessary to extract the ether layer with sodium hydroxide?

Solving for the products of reactions

(See attached file for full problem description) --- 1. Fe²+ and Sb³- 2. Mg²+ and As³- 3. Al³+ and O²- 4. Co³+ and I- 5. Sr² + and P³- 6. Ca²+ and C4+ 7. Fe³+ and As³- 8. Na + and S² ˉ Write the name or formula for these compounds: 1. tin (II) acetate 2. bromous acid 3. copper(II) permanganate

Mechanisms for three reactions

Sn + 2I2 ---> SnI4 (Ac2O,AcOH,reflux on arrow) SnI4 + 2PPh3 ---->(PPh3)2SnI4 (CHCl3 on arrow) SnI4 + (Me2SO)2 ----> SnI4(Me2SO)2 (CH2Cl2 on arrow) Give mechanisms for these reactions if there is any.

Solubility Problems with Ksp

Q#1 (Common ion problem) What is the solubility,in mg/mL of BaF2 in a)Pure Water b)in a solution containing 5.0mg/mL of KF Ksp of BaF2=1.0*10^-6 Q#2 Effect of pH on solubility a)Calculate the solubility of a saturated solution og Mg(OH)2 on pure water.(My answer is 1.65096*10^-4M b)Calculate the solubility of the sa

Hess' Law of Additive Equations for Reactions

Using Hess' Law of additive equations, rearrange and/or multiply the following reactions in order to find the enthalpy for the radical reaction between hydrochloric acid and isopropyl alcohol (CH3CHOHCH3) to form water and isopropyl chloride. The dots you see indicate a radical, which is much different than an ion or an element

Solubility and Titration

(See attached file for full problem description) --- 1. Tooth enamel consists of hydroxyapatite, Ca5(PO4)3OH (Ksp = 6.8x10-37). Fluoride ion added to drinking water reacts with Ca5(PO4)3OH to form the more tooth decay-resistant fluorapatite, Ca5(PO4)3F (Ksp =1.0x10-60). Fluoridated water has dramatically decreased cavities

Lab experiment titrating hydrochloric and acetic acids with NaOH

I would like to see the details of the calculations. For my lab experiment I have the following data: Titration 1: 25.00mL of unknown concentration HCl 2 drops of phenolpthalein to show end-point 1.0M NaOH What is the molarity of the HCl? What is the Ka of the HCl? What is the equivalence point? What is the half-equival

Titration Calculations

Note: You may assume that the densities of all solutions are 1.00 g/mL unless stated otherwise 1. A 10.00-mL sample of a solution containing the weak acid, formic acid, was placed in a 25-mL volumetric flask and diluted to the mark with water. A 10.00-mL sample of the diluted formic acid solution was then titrated with 0.13

Using Titration Techniques

1. If a strong acid and weak acid have the same concentration of acid, explain why they will have a different pH. 2. Explain why it is important to prime the pipette. 3. When using the titration technique explain why the beakers that contain the acid solutions must be dry before the acid is added, but the volumetric flask

Solubility Characteristics of Carboxylic Acids

1) If you took a pea-sized amount of salicylic acid and added 2 mL of demineralized water, what would the solubility of salicylic acid in the water be? 2) If you then added 5 drops of 6 M NaOH to the mixture, what would the solubility of salicylic acid in a base be? 3) I know the result of this is sodium salicylate, whi

Weak Base Reaction Calculations

Can someone please walk me through how to do the following problem: If a solution is made by mixing 20.0 ml 0.4 M NaCH3COO with 30 ml 0.4 M CH3COOH, calculate the pH. For acetic acid, ka = 1.76 x 10^-5.

Acid dissociation reaction.

Can someone please walk me through how to do the following problem? Thank you! Consider the following equation at equilibrium. CH3COOH <---> CH3COO- (aq) + H+ (aq) If NaCH3COO is added to the solution, indicate if the following quantities will increase, decrease, or stay the same -- and explain why for each. [H+] [O

Calculating Ka for Formic Acid

Can someone please walk me through how to do the following problem? Thank you! For a 0.13 M solution of formic acid, HCOOH, the pH = 2.40. Calculate Ka for formic acid. HCOOH <---> HCOO- (aq) + H+ (aq)